Mesoblast Announces Approval of First Osteoarthritis Clinical Trial Utilizing Adult Stem Cells

Press Release, January 20, 2009

The Australian company Mesoblast has received institutional ethics approval to begin clinical trials with its adult stem cell product, RepliCart, in the treatment of osteoarthritis of the knee.

Headquartered in Melbourne, Mesoblast is now approved to begin randomized, placebo-controlled, double-blind Phase II clinical trials for its off-the-shelf allogeneic stem cell product, "RepliCart", in the treatment of osteoarthritis of the knee in patients who have undergone reconstruction of a ruptured anterior cruciate ligament (ACL) within 6 months of a traumatic knee injury. The clinical trials will enroll 24 patients between the ages of 18 and 40 who will either be administered RepliCart in combination with hyaluronan, or just hyaluronan alone. The primary endpoint of the study will measure safety at 12 months, and a secondary endpoint will measure the prevention of cartilage loss and of knee osteoarthritis over time. Preclinical trials were successful in demonstrating the ability of a single injection of the allogeneic stem cells contained in RepliCart to regenerate joint cartilage and prevent osteoarthritis in animal models.

According to orthopedic surgeon Andrew Shimmin, from the Melbourne Orthopedic Research Foundation and the lead investigator of the clinical trials, "ACL injury is very common in our young active sporting population and unfortunately the injury is associated with the early development of arthritis despite modern reconstructive procedures. Little has changed in the prevention and treatment of arthritis over the past 50 years, so the application of Mesoblast's stem cell technology for reducing the progression of this degenerative process in the knee offers a new and exciting direction for the management of arthritis."

As Mesoblast's executive director, Dr. Silviu Itescu, explains, "Commencing this clinical trial in post-traumatic knee osteoarthritis is an important step towards accessing the huge commercial opportunity that exists today for Mesoblast in the osteoarthritis market."

It has been estimated that more than 15 million people in the U.S. alone suffer from osteoarthritis, which is a degenerative disease characterized by loss of cartilage. Osteoarthritis constitutes the most common form of musculoskeletal disorders among the elderly, in whom it is the primary cause of disability and joint pain. In the past, joint replacement has been the only option for such patients, but now stem cell therapy offers the first type of treatment that may actually reverse damage and regenerate joint tissue.

For people who suffer a ruptured anterior cruciate ligament (ACL) of the knee, which is more commonly and simply known as ruptured knee, 70% of the patients will develop osteoarthritis 15 to 20 years earlier than the general population, regardless of whether or not they have undergone reconstructive knee surgery. In the U.S. alone there are approximately 300,000 new cases per year of osteoarthritis having developed after an acute traumatic incident, not only in the elderly but in people of varying ages.

Mesoblast Limited is focused on the treatment of orthopedic conditions via the rapid commercialization of proprietary adult stem cell products that are designed for the regeneration and repair of bone and cartilage. As such, Mesoblast has the worldwide exclusive rights for a series of patented technologies that were developed over a period of more than 10 years and which are built upon the utilization of adult mesenchymal precursor cells (MPCs). As described on their website, Mesoblast has acquired 39% equity in Angioblast Systems Inc., which is a private New York-based biotechnology company that is developing the platform MPC technology for the treatment of cardiac, vascular and eye diseases including the repair and regeneration of blood vessels and heart muscle. Together, Mesoblast and Angioblast are jointly funding and advancing the core technologies behind such therapies.